One proof that this is a potential mechanism of resistance is our previous observation that as a response to anti-EGFR therapy, TFAP2A mRNA level is upregulated with only 24 h of therapy initiation in vitro.12 The TFAP2A transcription factor has dual-function and can play a role as a tumour suppressor gene (transcriptional repressor) or oncogene (transcriptional activator), depending on the tumour type. The gene discussed is EGFR; the disease is neoplasm.